Telegraph system



1,616,326 C. F. NELSON lTEH'JEKRAPI SYSTEM Filed Aug. 6, 1926 3 Sheets-5h69?I l RN. Ll 1111 NN W1 N5@ BNQ w g MNIN ln flttor nu' Feb. l, 1927.

C. F. NELSON TELEGRAPH SYSTEM Filed Aug. 6, 1926 3 Sheets-Sheet 2 Patented Feb. 1, 1927.

UNITED lSTATES PATENT OFFICE.

CRESCENT F.- NELSON, OF NEW DORP, NEW YORK, ASSIGNOR TO THE WESTERN UNION TELEGRAPH COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NE You.

TELEGRAPH SYSTEM.

AApplication led August 6, 1926. Serial-No. 127,874.

My invention relates `to a telegraph code system employing signals of plus, min-us and zero elements. Heretofore it Ahas been found impractical to employ universal double curi code is operated through universal double current repeaters.

Another object of my invention is to provide means whereby the zero current element of a three element recorder code comprising plus, minus and zero elements is eliminated.

n Another' object of my invention is to provide means whereby a single dot signal is split up. into two signals of plus and minus,

and in this form transmitted to the line as a single complete cycle,

Another object of my invention is to provide means whereby the dash signal is transmitted as a single plus'impulse, equal in length to two dot impulses, and a zero impulse is transmitted as a single minus impulse, equal in length to two dot impulses.

Another object of my invention is to pro- -vide means for maintaining two rotating members in synchron-ism employin a code in which the zero element of a t ree element recorder code is eliminated.

There are other (ibjects of my invention which, together with the foregoing, will appear in the specification which follows.

In general my invention comprises an karrangement 'at the transmitterXwhereby the (lot impulse is split up intoA a positive and a negative signal by means of a condenser discharge arrangement, ,a dash impulse is,

made equal to a single plus lmpulse equal ih length to two dot'impulses, and a zero impulse is translated into a single minus impulse equal in length to two dot impulses, and there are re-translated by means of a distributor at the .distant station into the original plus, minus and lzero code.

Referring tothe drawingsFig. 1 is a diagramn'latieillustration showing the circuits at the transmitting and receiving stations employed in practicing my invention;

Fig. 2 discloses a modified circuit arrangel ment for converting the cable code signals received over a submarine cable into double current signals;

Figs. 2 and 2B show the current waves;

Figs.l 3, 4, and 5 disclose the circuit arrangements;v and Fig. 3A the current impulses transmitted for maintaining synchronism in my system when the tape has run out. j

Referring more particularly to Fig. 1, the transmitter station A and the receiving station B are connected by a signalling line 3. The tape 4 operates through the feelers 5 and 6 of a tape transmitter WT of the well-known Wheatstone type, to selectively close contacts 7 and 8. The transmitter relay TR is provided with three windings 10, 11 and "12 for actuating the armature 14 to its right or left hand position for transmitting impulses over the line 3.

The circuits for the relay windings 1() and 11 are completed through contacts 7 and 8` respectively and through contact 30 which closes once during each revolution ofthe cam shaft 9. The contact 30 thus 'controls the transmission of the Iimpulse to make it of a definite predetermined length, the details of which are describedK in the patent to Foley, No. 1,517,110. By adjusting the position of the cam 3()a on the striker .through the solid ring 17 and segmented ring 17 of the rotary distributer RD to operate the selecting relay 18. ings 19 to 23 of the sending-on relays S and S2 and the automatic synchronizing relay S3 are responsive' to these received impulses in a mannerto be hereinafter described for controlling the code recorder 24 which may be a direct writer. The solid and segmented rings 25 and 25 of the rotary distributer operate in conjunction with the corrector relay 26 for maintaining the distributor in synchronism with the tape The windrings .201 to 203 of the rotary distributer RD2 function to translate the three element `recorder code into'double vcurrent signals of v plus and minus by operating the windings 204 to 207 of the local transmitting relay S* in a manner hereinafter described for transmitting impulses over the conductor 208 to operate the line transmitting lay 209.

Referring to Fig.. V3, the windings- 301 to 304 are the energizing windings of s -nchronizing relays S?, S, controlled by t e cam member 305 through its contactor 306 for controlling the windings 307 to 309 of transmitting relay S's for transmitting synchronous impulses when the tape'310 has run out.

and the cam member 311 closes its contact..A

In order to better understand the invention a detailed description of the operations which take place when the code s1 al impulses are transmitted will be described. It will be assumed that the tape 4 (see Fig. 1) is so perforated as to transmit first a dot, then a dash, and tinally a s ace signal. Nori mall it will be understoo that upon every revo ution of the cam shaft 9 ofthe Wheatstone transmitter WT, an energizin circuit is completed for the relay TR from t e negative battery through the relay winding 12, resistor 31, closed contact and resistor 82 to positive battery. This current, however, is overpowered when current flows in either of the other windings 10 vor 11.

In order to transmit a dot impulse, the tape is so perforated thatas the pin feelers are moved upwardly, the feeler l6 passes through a 'perforation 4'L (see Fig. 1^), thereby closing the contact 7 and a circuit is completed from the positive battery through resistor 32, contact 30,v through the contact 7 and through the relay winding 11 to negative battery. A arallel'circuit is completed throu h the con enser K', relay winding 10, and t rough relay winding 11 to negative battery. The energized winding 11 causes the armature 14 to move against its left hand contact. A positive impulse is thus trans- `mittedv from positive battery, through the resistor 37, the left lhand contact 4and arma-u ture 14, llne 3, through the winding'of main llne relay MR at station B and winding of Y corrector relay 26 to return' ground.

The contacts 7 and 8 are so adjusted that the circuit above traced for the relay rwindlngs 11 and 10, remains closed only for a length of time equal to one half of the dura=l tion of time allotted to a.l complete dot impulse. ',When this circuit is o cned, the charged condenser K discharges t rough the windin 10 in a reverse direction and this causes t e armature 14 to move from its left `70 yhand to its righthandA contact. An impulse is -thus transmitted from negative battery through the right hand contact and armature 14, `the line 3, to station B and through the windings of main li'ne relay MR and corrector relay 26 to return ground. Itv will thus be seen that lthedot impulse has now been translated into a cycle equal in length winding 11 from positive battery, through l resistor 32, contact 30, contact 8, resistor 39y and relay winding 11 to negative battery.

The relay winding 11 is energized and moves the armaturev 14 -to its left hand contact, so

that a circuit isl completed over the line from positive battery through resistor 37, the

left hand contact and armature 14, line 3, to station B, and through the relays 15 and 26..' The armature 14 remains against its left hand contact for the full duration of time assigned'to a dash impulse.

When a space impulse is to be transmitted there is no erforation to rmit the pin eelers' an 6 to pass, as indicated at 4*, and hence the contacts at 7 and 8 remain open. Upon the rotation of the cam shaft 9 however,`the striker bar 9 moves upward andv closes a circuit for the relay winding 12, from positive battery through resistor 32, the contact 30, resistor' 31 and relay winding 12 to negative battery. The armature 14 is thereby moved to 'close its' right hand contact and a negative impulse is transmitted from negative battery through lthe resistor, the right hand contact and armature 14, line 3, to station B, and the windings of relays 15 and 26 to the ground return.

From the above description it will be evident that the three element impulses of dot, dash and zero have been translated from the usual positive, negative and zero current impulses indicated in Fig. 1B, into a dot impulse comprising a positive-half and a negallO tive half, a dash impulse comprisinga full length positive impulse and a zero impulse comprising'afull length negative impulse as indicated in Fig. 1C. The manner in which these impulses are translated back into their original condition at the receiv ing end will now be described.

Upon the receipt of the first positive impulse comprising the first half of the dot cycle, the main line relay MR at station B is energized over a circuit previously traced, and the armature 16 is moved against its left hand contact. At this instant, the brush b" which rotates over the rings 17 and 17 of the rotary distributer is on'its irst segment and a circuit is therefore completed for the selecting relay 18'from the positive battery through the left hand contact and armature 16, the distributer ring 17, and rotating'brush b', the first contact of the distributor and through the winding of selec-ting relay 18 to the return ground. The relay 18 is thus energized and .moves its armature40 to its left hand contact.

As the second half of the dotimpulse is being received which, it will .he recalled, was of a negative polarity, (see Fig.A 1C), the brush b moves onto the second Segment of the distributer ring 17. This negative impulse received over the line.v 3 energizes the main linerelay MR so as to move its armature 16 against its right hand contact. `A circuit is ,thereby completed Vfrom the negative side of the battery through the right hand contact, and armature 16 and over the distributery ring 17, brush b and its second segment, through the armature 40 and its .left ,hand contact and thence through the windings of the sending-on relays S2, S', to the return ground. The relay winding ,19 is designed to be responsive to this negative impulse.

by operating the armature 41 to the right to complete a local circuit from the negative battery through the right hand contact and armature 41, through the recorder 24,` the armature'42 and its left hand contact to positive battery. A dot impulse is thus recorded at 24.

The dash signal now arrives, consisting, of a positive impulse having av full period duration and henceequal to the two half period dot impulses, (see Fig. 1C). The tirst half or selecting position of the impulse will energize the relay MR and cause it, to move its armatu e 16 against its left hand' contact. At this i instant the distributer brush b is on its third segment and an enf crgizing circuit will be completed for` the selecting relay 18 similar to that heretofore traced. The relay 18 will' therefore move its armature 40 to its leftv hand Contact.

As the second or signaling portion of this dash impulse arrives, the distributer brush b is on its fourth segment.` The received impulse in this case being again positive, thearn'lature 16 of the relay MR will remain .against its left. hand contactand a circuit will he completed for the windings I9 and 20 of the sending-on relays, similar to that heretofore traced except that this time` the pol-arity of the impulse will be positive. As a result the relay winding '20,

' `constructed to be responsive to a positive the dot relay moves to itslleft hand contact so that it is recorded on recorder 24. Y-The l I circuit for this `impulse will .be similar to versed in polarity.

p The space signal now arrives, composed of two half period minus elements, i. e. a minus impulse equal'to a full time period, (see Fig. 1C). It will be remembered that a space impulse is sent by the transmitter VT when thepin feelers 5 and 6 strike' an unperforated part of the tape so that the contacts at 7 and 8 remain open. An impulse is then sent over a circuit from .positive battery through contact 30, resister 31 and relayv winding 12 to negative battery. This causes the armature 14of transmitter relay TR -to move against itsright hand contact and sendy a negative impulse over line `3 to station B. The armature 16 of main line relay MR moves against its right hand contact and thisin turn operates the select-ing relay 181 through segment 5 of ring a zero or space is recorded for the space signal. This completes the recording of the character A in the manner indicated From the description thus far traced, it

=wil1"be evident that the first impulse in each case is the selecting impulse, while the secondimpulse transmitted over the line from the sending to the receiving sta-tion yis the signaling or markin element.

" In cases iwhere cable code signals are received over a submarine cable and are to be transmitted over an aerial orland line, a

rotary distributer is provided for the purpose of translating the cable code signals Vinto double current signals. .In this instance, the rotary distributer functions in a manner similar to the tape transmitter of for the letter A shown in 2A, is being received over the submarine cable by.-

the cable relays CDR and CDR2 and is to be translated into the double current signal as shown in Fig. 2B. When the dot impulse is received over the cable, the armay ture 210 of thedot cable relay CDR movesA S* t0 negatlve battery. This causes armature 211 to move to its left hand or positive battery contact. A ,slight locking current from battery LB holds the armature lightly.v

against either of its cont-acts.

The next impulse received over the cable, is a dash impulse, which is a full length negative impulse, as indicated in Fig. 2A. The`dash cable relay CDR'2 responds and moves its armature 222 against its front orright hand contact, thus closing a circuit from positive battery, through armature* 222, segment 3 of the dash ring 203, brushsolid ring 203', condenser K4l and winding 206 of the local transmitting relay S* to negative battery. The armature 211 moves against its left hand contact,I and closes a circuit from positive battery,l through armature 211, conductor l2, and winding 209 of line transmitting relay LTRZ.l Accordingly, armature 212 moves against its' left hand Contact and sends a positive impulse over the line L2. The condenser K* discharges through resistor 208 so that the armature 211 remains against its left hand contact while the brush b5 passes over4 thethree se ments following segment 3, and hence a fu l length positive impulse, (equal in length to the two-element dot signal as indicated in Fig. 2B) is transmitted over the line L2. The dash'cable relay now opens, 'so that both cable relays CDR and CDR2 are on their back contacts.

` The next element of the letter A is a' space or zero impulse, as indicated in Fig. 2^. As above stated, the armatures of both cable relays are now on their back stops but. as the brush bs moves onto segment 4'of the spacing ring 201 a circuit is closed from positive battery, through segment 4 of ring 201, brush b3; solid ring 201', condenser Kz and winding 204 of local transmitting relay This causes armature 211 to move over against its` right hand contact where it remains until the next dot or dash signal 1s received.` A negative impulse, (equal in length to the two-element dot signal), 1s

- therefore transmitted by the linetransmit ting relay LTR? over the line L2. Hence the zero element received at the cable relays, as indicated in Fig. 2^, is translated into a any of the other coils of the relay. To this y end the spacing condenser K2 is made approximately one-thirdthe capacity ofthe dot and dash condensers K8 and K4. l

A As the brush b* moves onto the discharge segment 1the circuit just traced for the relay Winding 205 is opened, and the condenser K3 `discharges itself via the brush b* and said segment 1', through said relay winding 205. This momentary reverse current through the relay winding causes the armature 211 to be moved to its right hand contact. This closes a circuit from positive battery through armature 211, conductor 1', and winding 209 of line transmitting relay LTR2 to negative' battery. Armature 212, therefore, moves against its right hand contact and sends a negative impulse over the line L2.- The single full length dot impulse indicated in Fig. 2^ and received by the cable dot relay CDR has thus -been split into two half 'length impulses one ositive and one negative, as indicated in and transmitted into the line L.

In this manner not only may the'threeelement code signals received from the ta e be translated into the double current co e described, but likewise impulses of the threeelement code type received over a cable ma be translated for transmission over a signa ling line'. Fig. 3 discloses the arrangement by which the double current code may be employed for transmitting synchronizing impulses when the tape has run out. The details of the tape operative cam mechanism disclosed in'Fig. 3 have been previously described in theI U. S. patent to Peterman No. 1,542,779 llnd hence need not be described in detail ere.

Instead of connecting the contact memig. 2B

eoV

bers 7 and 8 directly to 'the windings 307 to 309 of the transmitting relay S, they are connected 'thereto through thel contacts of uwindings 301 and 302 of the synchronizing shown, the winding 301 is shunted out in the obvious manner disclosed. As the cam member 305 rotates the lever member 306 closes its lower contact and the winding 302 is shunted out.

Uplon the energization of the winding` 302 at t e instant when the' winding 301 is.`

shunted the armature 318 is ymoved to its lowerl contact c. Upon the movement of the cam member so as to shunt the winding 302 the relay winding 301 is energized and moves'the armature 317 to its lower contact c. -In this manner the `windings 307 and .308 of transmitter relay Ss are alternately venergized to transmit to the line L3 the dot and dashy of the two-element signals indicated in Figi-3l?.

- When the llever 306 is on the smooth portion ofthe cam305 the Contact arm of the lever will be held 1n mid-position so that both relays S5 and Ss will be energized and their armatures 317 and 318 will be held on their open contacts c. During this interval, a circuit is closedrom positive battery, through' contact 30 conductor 315, and windin 309 of transmitter relay S8 which causes its armature 316 to move against its right hand contact, thereby sending a prolonged negative space impulse to line L8, rt'rual to 14 signal impulsesas indicated in 'he manner in which the ,brushes ofthe rotary distributers at the'oppositeends of the line are maintained in synchroism and in exact vphase relation is well known to thoseL 'familiarwith the operation of teleaph systems. It is fully described in U. gl patent to Yorke and Benjamin, 1,298,622, dated March25, 1-919. It is suihcient, therefore, to merely indicate diagrammatically the synchronizing elements and to briefly mention the` operation.y

Accordin to the Yorke-Benjamin correction metho ,each current reversal alecting the correcting relayf26 aords ani opportunity for correction, but the correction mechanism operates only when, at the time.

lof one or more reversals, one distributer is suiciently outof phase with respect to the other (listributer, to require correction.

`'ilhe 'armature of relay 26 vibrates in unison with the vibration ofthe armature 16- relay 54' to rin 25 of distributor RD, and thence through rush b', the connected segments of ring 25 and winding of the make relay 54 to negative` relay 55 to negative battery. If, however, the brushes of the distributers are in proper phase relation, the brush b2 will be over one of the insulated segments of the ring 25 at the instant of each completion of a circuit through conductor 53, and through theA winding of relay 54 and before the brush b2 can have passed on to one of the conduc# tive segments of ring 25', relay 54 willhave attracted its armature, thereby breaking the circuit to the ring 25, so that the ma net 55, will--not be operated. But if at the instant the armature 56 completes a circuit through conductor 53, the brush b2 is on one of the conductive segments of ring 25', (which will occurif the two distributers are not in exact proper phase relation), a circuit will be completed through the windin of the make relay 55. The armatureof rel5hy455 will be attracted against its front contact, thus' closing a circuit from positive battery 'through armature and ront contact of relay 55, and the winding of tle 4mechanical corrector magnet 57. The armature of magnet 57 4actuates lthe corrector mechanism which steps the brushes of rotary distributer RD backwardV to bring them into proper phase relation with the brushes of the distributer at the opposite end of the line'or cable.

If on account of line trouble or other cause, the brushes should become so far out of proper-phase relation that with the transmitted signal impulses the selecting portions of the two-element characters are received when the brush b is on the even segments,

make relay 55 as lfollows: from positive battery through conductor 58, armature 23, conductor 59, conductor 60, and winding of relay 55 to negative battery. This circuit will be established every time the brush b passes over one of the even se ments and each time the armature of the re ay 55 is attracted, a circuit is closed through the winding of the mechanical corrector magnet 57, which results in step ing the brushes of the distributer backward This will continue until the brushes are again brought into proper phase relation with the transmitter at the sending station, when the brush B is on. the odd segments during the reception of the `selecting portion of the signal impulses. Thefarmature 23* will be moved to its back contact under the action of the biasing windloo' ing 23" through which a weak current is constantly iowing. This biasing winding is used instead of a spring.

I have described the several features of my invention particularly is illustrated in the accompanying drawings but Iam not limited in the scope or application of this invention except as set forth in the appended claims.

I claim:

1. In a telegraph system, a transmitting station, a receiving station, a signalling line connecting said stations, means at said transmitting station for transmitting a three element code of plus, minus and zero elements, means at said first station for translating said code into two element signals oit' plus and minus impulses, and means at said second station for ire-translating said code of plusand minus impulses into said originalv code of plus, minus and zero impulses.

2. In a telegraph system, a transmitting station, a Vreceiving station, a tape' at said first station perforated to transmit a three element code, means at said first station for translating said three element code into a two element codey and means at said second station for translating said two element code into athree element code.

3. In a telegraph system, a transmitting station, a receiving station, a line connecting said stations, a tape perorated with a three element code of plus, minus and zero elements, a repeater rela controlled by said tape or 'translating sald three element code into a two-element code and means at said receiving station responsive to said two-element code.

4. In a' telegraphic system, a transmitting station, a receiving station, a tapey perforated with the three elementcode including zeroas one of its elements at said transmitting station, a transmitterl at said first station controlled by said tape, means at said first station for translatin'- said code into a two element code, a distriImter at said second station operating synchronously with said tape-controlled transmitter, circuit arrangements including said distributer for translating said two element code into the original three element code and a recorder responsive to the said three element code.

5. In a telegraph system, a transmitting station, a receiving station, a tape perioratedA with the three element code including zero as one of its elements at said transmitting station, a transmitter said first station controlled hy said tape, means at said iirst station for translating said code into a two element code, a distrihnter at said second station operating synchronously with said tape-controlled transmitter, circuit arrangements including said distrihnter for translating said two element code into the originalthree element code, a recorder responsive to the said three element code, and means automatically responsive when said tape runs out for maintaining said transmitter and said distributer in synchronism.

6. Inatelegraph system, a transmitting station, a receiving station, a tape perforated with 'the three element code including zero as one of its elements at said transmitting station a transmitter at said irst station controlled .by said tape, means at said first station for translating said code into a two elementv code, a distributor at said second station operating synchronously with said tapecontrolled transn'iitter` circuit arrangements including said distributer for translating said two element code into the original three element'code, a recorder responsive to the said three element code, and means automatically responsive when said transmitter and said distributer fall out of synchronism for bringing them lback into synchronism.

7. In a telegraph system, a transmitting station, a receiving station, a tape perforated with the three element code including zero as one of its elements .at said transmitting station, a transmitter at said first ystation controlled by said tape, means at said irst station for translating said code into a' two element code, a. distributor at said second station operating synchronously with said tape-controiled transmitter, circuit arrangements inclnding said distributer for translating said two element code into the original three element code, a recorder responsive tothe said three element code, and means automaticall responsive when said tape runs outfwhereiiy a predetermined combination of said two element code in periodically transmitted for maintaining said transmitter and said distributer i'n synchronism.

8,'In a telegraph system, a transmitting station, a receiving station, a line connecting 'said stations, a three element code transmitter at said transmitting station, a three element receiver at said receiving station, means whereby said transmitter controls said -receiver over said line, and means whereby only a two element code is transmitted over said line.

9. The method of transmitting telegraph signalswhich comprises making a tape record oi a three element code, translating said three element code into a two element code, transmitting said two element code to a receiving station, translating said two gelernent code into its original form as a three element code and operating a recorder with three elementcode.

testimony whereof I aiix my signature.

onnsoanr r. saison. 

